


Dead Wrong

by therunawaypen



Series: Sherlock Tumblr Prompt Fills [1]
Category: Sherlock (TV)
Genre: AU, Alternate Universe - Canon Divergence, Alternate Universe - Dark, M/M, Serial Killer John, Serial Killers, dark!john
Language: English
Status: Completed
Published: 2013-09-09
Updated: 2013-09-09
Packaged: 2017-12-26 02:35:56
Rating: Mature
Warnings: Graphic Depictions Of Violence, Major Character Death
Chapters: 1
Words: 2,170
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/960569
Author URL: https://archiveofourown.org/users/therunawaypen/pseuds/therunawaypen
Summary: <blockquote class="userstuff">
              <p>Sally told John that one day Sherlock would be the reason for a dead body. She was wrong. Dead wrong</p>
            </blockquote>





	Dead Wrong

**Author's Note:**

> Thanks to davidtennant-is-my-spiritanimal and ill-sherlock-the-door from Tumblr for the prompt. 
> 
> I hope I was able to give you what you wanted!

In all her years working at New Scotland Yard, Sally Donovan would like to think that she had picked up on quite a number of things (regardless of what that freak Sherlock suggested).

So when she woke up in handcuffs, she knew something was wrong. When she opened her eyes and saw that she was in her basement, not her bedroom, she knew she was in trouble. And when she saw John Watson laying across from her on the cold concrete floor, she knew she wasn’t the only one.

“Sally? What the blazes is going on here?” John asked, rubbing his head like he had been struck, “Where the hell are we?”

“We’re in my bloody basement.” Sally struggled to get into a sitting position, “Can you pick a lock?”

John raised an eyebrow, “Living with Sherlock, I learned fast.”

“Well get me out of these damn handcuffs then!”

The former soldier nodded, making his way over to Sally, “Do you remember what happened?” he asked quietly, working at her handcuffs.

“I just went to bed after spending too bloody long on that open murder investigation.” Sally grumbled, “What about you?”

She could hear John sigh behind her, “We were out of milk again, Sherlock had me run to the store. I guess I should learn to stay away from alley shortcuts.”

“What the hell were you thinking? You knew there were psychos running about London.” Sally rubbed her wrists as her hands were freed from the cuffs.

John shook his head, standing, “There are always psychos running about London, Sally.” He grumbled, “Now why are we in your basement?”

“Hell if I know.” The police sergeant shook her head, “I need to get upstairs, hopefully I can get to a phone or my gun. Unless you’ve got either of those on you.”

Again, the doctor shook his head, “I doubt any criminal is dumb enough to leave someone armed and unattended.”

Sally rolled her eyes. It was true, even the lowest drug dealer or strung out smuggler knew to remove any weapons from hostages, “Come on then. Let’s go. Quickly, before he gets back.” She mumbled, already making her way up her basement stairs with John following her.

She was halfway up the stairs when something crossed her mind. If even the dumbest of criminals removed weapons from hostages…why only handcuff the female and leave the male untied?

“Hey John? Why do you suppose he didn’t tie you up?” She asked. And now that she thought about it, “And what did you use to pick my locks?”

John didn’t answer. But the soft _click_ she heard behind her was a deafening answer enough. When Sally Donovan turned around, she was facing the barrel of John Watson’s gun, pointed between her eyes.

“What…John, what are you…” She couldn’t even form a question. What question could she even form?

John smiled softly, a sweet, unassuming smile for someone aiming a weapon at a woman in her pajamas. “I was wondering when you would figure it out. I almost thought you wouldn’t think of it at all. But you are smarter than Sherlock gives you credit for.”

Sally could feel every muscle in her body wanting to react to the weapon being pointed at her. It took everything in her to not react rashly. Every movement could be her last, “I always knew that freak was going to snap one day…” She murmured, gripping the handrail of the stairs.

“Oh Sally, you still don’t get it, do you?” John laughed lightly, the same way he would at one of Lestrade’s jokes, “The first time we met, you told me that someday Sherlock wouldn’t be content to solve crimes, he’d start committing them. That one day, we’d all be standing over a body _he_ killed.” He sighed softly, but the gun pointed up at Sally’s forehead never wavered, “But you were wrong on two counts.”

“Oh?” Sally gulped, trying to keep herself calm. She had the higher ground, being higher on the stairs than John was. If she could find her opening, if she could keep him talking long enough for him to make a mistake… “How so?”

John smiled again, the same one he used when he was being polite, “First, that Sherlock would resort to killing because of his love of murder investigations. For a brilliant mind like Sherlock’s, going too long without a puzzle to solve is madness. He needs the stimulation, the rush of a mystery, the thrill of the pieces coming together.” He shook his head ever so slightly, eyes never leaving Sally, “Murder isn’t a puzzle, it’s a purely physical activity. It would never feed Sherlock’s brilliance, his _soul_ , the way he needs.”

There was something in the tone of John’s voice that was sickeningly familiar. It was the same tone John used whenever he murmured “Fantastic” or “Brilliant” at one of Sherlock’s deductions.

Sally licked her lips out of nerves. “And…the other thing I was wrong about?”

This just made John laugh again, his good mood making shivers run up her spine. “Between the two of us: Sherlock and I, only one of us is a trained killer.”

It was then that Sally remembered that John was not a mild mannered doctor. He had also been a soldier, a killer.

“So what is this? Some sick gift for the freak?” It probably wasn’t smart, calling Sherlock “freak” in front of John, but the habit was a hard one to break, “You kill me so Sherlock can solve my murder?”

“Oh Sally, you think this is the first time I’ve killed for Sherlock?” John tutted at her in a condescending manner, “Remember the cabbie?”

The first case John had worked with Sherlock. They had never identified the shooter in that case, “But you hardly knew Sherlock…” Sally wished her voice sounded stronger.

“Sherlock gave me a reason to _live_ again.” John’s voice was _filled_ with adoration for the self-proclaimed sociopath, “He gave me a battle to fight, he gave me a _mission._ ”

“So he tells you to kill, and you kill?” Sally chanced another step backwards up the stairs. She had one foot on the higher step, but the furrowed brow on John’s face was more than enough clue that he was not pleased.

“Of course he doesn’t _know_ what I’m doing.” John chuckled, “Sherlock, despite his quirks and poor moods, fights on the side of angels.” The light look on his face vanished, revealing the stony gaze Sally had seen him put on in front of suspects, “He doesn’t know evil the way I do.”

“Then you know that you’ll get caught.” Deep down, Sally knew that she only had one chance, either to tackle John head on, to go for the gun, or to turn and run. Ultimately, the second option was the only one that didn’t seem like instant suicide.

The next sound from John wasn’t a soft sigh, a light chuckle, or even his jovial laugh. It was a cackle, a manic string of guffaws and hisses, “Oh Sally, you think you’re the first _planned_ murder I’ve done?” He grinned, “How many of your cold cases do you think are my masterpieces?”

That thought made Sally’s blood run cold. In the years since John had joined Sherlock in his little “consulting detective” game, there had been nearly a dozen cases that had gone cold, some of them Sherlock had actively worked on, other, Lestrade only gave him the file after the cases had gone cold.

“Unsettling, isn’t it?” John grinned, showing a few too many teeth for Sally’s liking, “It takes me _months_ to plan out each murder, to make sure _each and every_ detail is in order. Everything needs to be done perfectly, I can’t have Sherlock thinking my crimes are “simple” now, can I?”

It was now or never, Sally decided, swinging her fist at John’s gun hand. The gun went skittering across the basement floor, but Sally didn’t watch the gun, she was already running up the stairs. She could hear John’s footsteps behind her, but they were moving down the stairs, after the gun. If her mind wasn’t running on adrenalyn, she might have questioned why he was wasting such precious seconds going after a weapon.

She also might have seen wire across her basement door as she pulled it open with force.

But it was as she heard the muted gunshot, _felt_ the bullet tear through her ribcage and lung, that she saw the gun set up on a rig, just outside her basement door.

 _It had all been a trick.._ She realized as tumbled back down the stairs, blood filling her lungs. Of course it had been. She would have _never_ been able to knock a gun from a soldier’s grip. And as she hit the concrete at the bottom of the stairs, she could see the smile on Doctor John Watson’s face.

“Oh Sally.” He sighed, shaking his head as he stepped over her carefully. He was wearing crime scene booties now, she realized, to prevent him leaving evidence… “You see, but you don’t observe.”

As he stepped onto a clean part of the stairs, John looked at Sally’s wound, “That’s a nice shot,” he nodded, “Right through the lung. I was hoping I wouldn’t have to add a finishing touch. I do like to keep things hands off, it’s cleaner that way, less chance of mistakes.” He chuckled. “But then again, I’ve never killed someone I knew before. Perhaps you’ll be my big mistake, hmm? I guess we’ll see…or rather, I’ll see. You won’t be seeing much of anything soon.”

* * *

 

John wasn’t stupid. Seeing Jennifer Wilson’s crime scene had taught him to make sure a victim was good and dead before leaving the body. No need risking Sally leaving a beyond the grave message.

Thinking of “A Study in Pink” sent chills down John’s spine and a rush of blood to his groin. Sherlock’s mind and powers of deductions had not only unraveled the complexities of the case, they had unwrapped John’s entire being, leaving him bare before the genius.

Sherlock burned brightest when he was solving a complex riddle—no, _puzzle_. And nothing made John hornier than seeing Sherlock doing what he did best. He had been a fool before, dabbling with _women_ when he could have been having Sherlock. Women were boring—a cardinal sin with Sherlock—but Sherlock was eternal…

Once Sally had stopped moving, and more importantly, stopped breathing, he made his way up the stairs, careful not to disturb any of the lovely blood splatter left behind. He only stopped briefly to clean up the wire rig he had set up, leaving no evidence that it had even been there.

The rig for the gun itself was a simple design: have the trigger pulled as soon as the door opened past a certain point. Using Sally’s own gun in the rig, complete with homemade silencer, was a nice touch in John’s mind. After donning his surgical gloves, he carefully dismantled the rig and packed it away in a plain duffle bag, along with the silencer. Already in the bag was a plain white terry cloth dish towel, which John had poured chloroform on and held over Sally’s face while she slept (not adding _too_ much pressure, no need to leave marks).

The gun, he left on the kitchen table. There was no sense taking it, it would only connect him to the crime. And as for the hair and other evidence to him being in Sally’s basement? Well, that was Sally’s fault for hosting the NSY Christmas Party days before. Nearly half of New Scotland Yard had been in the basement getting drunk, so there would be evidence of a number of people in the basement, including John and Sherlock.

Not that Sherlock would _ever_ be considered a suspect. No, never again would Sherlock be the subject of an investigation. John _always_ made sure Sherlock had an alibi for the nights he did his…work. Tonight, he was visiting Mummy for the holidays. John was only still in London because he need to work a shift at the clinic...and create his newest masterpiece.

John walked down the shoveled path from Sally’s home, keeping his head down  to keep from being recognized. This would be the hard part: getting rid of the evidence. Luckily for John, he knew the best was to dispose of evidence was to take it directly to where _everything_ was disposed of. Investigations usually didn’t search landfills unless there was evidence that crucial clues had been thrown away. And even then, the chances of them finding anything were slim.

But even though John had a fondness for the occasional gamble, this was not something to wager on. Any evidence that might have his DNA would find its way into the trash incinerator faster than it normally would.

It was tedious work, but it was worth it.

Everything was worth it for Sherlock


End file.
